Snoring is the most common symptom, along with increased daytime sleepiness, in patients with obstructive sleep apnea (OSA). However, doctors often neglect snoring in clinical practice, and snoring is not addressed in the treatment guidelines of OSA. Therefore, study about snoring and its clinical implications in sleep medicine are needed. The natural history of snoring shows that snoring can evolve into OSA, and the most important risk factors for this continuum are obesity and male sex. Snoring can be a social problem causing annoyance and family difficulties. Animal and human studies have shown that snoring involves the four injury mechanisms of upper airway inflammation, peripheral neuropathy, parasympathetic hypofunction, and endothelial injury. Previous studies have reported that systemic diseases such as atherosclerosis, metabolic syndrome, hypertension, and cardiac diseases were comorbid with snoring. However, most of these studies enrolled patients characterized by survey or questionnaire; therefore, data were biased with effects of OSA. Thus, consensus on the definition and detection of snoring is lacking. Additional studies are required to determine the exact clinical implications of snoring.